Laser anneal is a commonly used anneal method in the manufacturing of semiconductor wafers. For example, source and drain regions of transistors are often formed by implanting p-type or n-type impurities. The implanted impurities may be activated using the laser anneal. During a typical laser anneal process, a wafer is scanned with a laser beam, which is projected on a small portion of the wafer at a time, and the laser beam steps forward until all of the wafer is scanned by the laser beam.